LINUX
Official Website :
http://www.linux.org/
The History of Linux began in 1991 with the commencement of a personal project by a Finnish student, Linus Torvalds, to create a new operating system kernel.
Since then the resulting Linux kernel has been marked by constant growth throughout its history. Since the initial release of its source code in 1991, it has grown from a small number of C files under a license prohibiting commercial distribution to its state in 2009 of over 370 megabytes of source under the GNU General Public LicenseHistory Of Linux
In 1991, in Helsinki, Linus Torvalds began a project that later became the Linux kernel. It was initially a terminal emulator, which Torvalds used to access the large UNIX servers of the university. He wrote the program specifically for the hardware he was using and independent of an operating system because he wanted to use the functions of his new PC with an 80386 processor. Development was done on MINIX using the GNU C compiler, which is still the main choice for compiling Linux today (although the code can be built with other compilers, such as the Intel C Compiler).
As Torvalds wrote in his book Just for Fun, he eventually realized that he had written an operating system kernel. On 25 August 1991, he announced this system in a Usenet posting to the newsgroup "comp.os.minix."
Hello everybody out there using minix -
I'm doing a (free) operating system (just a hobby, won't be big and professional like gnu) for 386(486) AT clones. This has been brewing since april, and is starting to get ready. I'd like any feedback on things people like/dislike in minix, as my OS resembles it somewhat (same physical layout of the file-system (due to practical reasons) among other things).
I've currently ported bash (1.08) and gcc (1.40), and things seem to work. This implies that I'll get something practical within a few months, and I'd like to know what features most people would want. Any suggestions are welcome, but I won't promise I'll implement them :-)
Linus Torvalds had wanted to call his invention Freax, a portmanteau of "freak", "free", and "x" (as an allusion to Unix). During the start of his work on the system, he stored the files under the name "Freax" for about half of a year. Torvalds had already considered the name "Linux," but initially dismissed it as too egotistical.
In order to facilitate development, the files were uploaded to the FTP server (ftp.funet.fi) of FUNET in September 1991. Ari Lemmke, Torvald's coworker at the University of Helsinki who was one of the volunteer administrators for the FTP server at the time, did not think that "Freax" was a good name. So, he named the project "Linux" on the server without consulting Torvalds. Later, however, Torvalds consented to "Linux".
Development of Linux
Kernel
There are many other well-known maintainers for the Linux kernel beside Torvalds such as Alan Cox and Marcelo Tosatti. Cox maintained version 2.2 of the kernel until it was discontinued at the end of 2003. Likewise, Tosatti maintained version 2.4 of the kernel until the middle of 2006. Andrew Morton steers the development and administration of the 2.6 kernel, which was released on 18 December 2003 in its first stable incarnation. Also the older branches are still constantly improved.
Community
The largest part of the work on Linux is performed by the community: the thousands of programmers around the world that use Linux and send their suggested improvements to the maintainers. Various companies have also helped not only with the development of the Kernels, but also with the writing of the body of auxiliary software, which is distributed with Linux.
It is released both by organized projects such as Debian, and by projects connected directly with companies such as Fedora and openSUSE. The members of the respective projects meet at various conferences and fairs, in order to exchange ideas. One of the largest of these fairs is the LinuxTag in Germany (currently in Berlin), where about 10,000 people assemble annually, in order to discuss Linux and the projects associated with it.
Open Source Development Lab and Linux Foundation
The Open Source Development Lab (OSDL) was created in the year 2000, and is an independent nonprofit organization which pursues the goal of optimizing Linux for employment in data centers and in the carrier range. It served as sponsored working premises for Linus Torvalds and also for Andrew Morton (until the middle of 2006 when Morton transferred to Google). Torvalds works full-time on behalf of OSDL, developing the Linux Kernels.
On January 22, 2007, OSDL and the Free Standards Group merged to form The Linux Foundation, narrowing their respective focuses to that of promoting GNU/Linux in competition with Microsoft Windows.
Companies
Despite being open-source, a few companies profit from Linux. These companies, most of which are also members of the Open Source Development Lab, invest substantial resources into the advancement and development of Linux, in order to make it suited for various application areas. This includes hardware donations for driver developers, cash donations for people who develop Linux software, and the employment of Linux programmers at the company. Some examples are IBM and HP, which use Linux on their own servers, and Red Hat, which maintains its own distribution. Likewise Nokia supports Linux by the development and LGPL licensing of Qt, which makes the development of KDE possible, and by employing some of the X and KDE developers.
Popular Linux Distributions
Well-known Linux distributions include:
- Arch Linux: a distribution based on the KISS principle with a rolling release system
- CentOS: a distribution derived from the same sources used by Red Hat, maintained by a dedicated volunteer community of developers with both 100% Red Hat-compatible versions and an upgraded version that is not always 100% upstream compatible
- Debian: a non-commercial distribution maintained by a volunteer developer community with a strong commitment to free software principles
- Fedora: a community distribution sponsored by Red Hat
- Gentoo: a distribution targeted at power users, known for its FreeBSD Ports-like automated system for compiling applications from source code
- Knoppix : the first Live CD distribution to run completely from removable media without installation to a hard disk, derived from Debian
- Kubuntu : the KDE version of Ubuntu.
- Linux Mint: a distribution based on and compatible with Ubuntu.
- Mandriva : a Red Hat derivative popular in France and Brazil, today maintained by the French company of the same name.
- openSUSE : a community distribution mainly sponsored by Novell.
- Oracle Enterprise Linux: which is a derivative of Red Hat Enterprise Linux, maintained and commercially supported by Oracle.
- Pardus: Turkey's national operating system developed by TÜBİTAK/UEKAE.
- PClinuxOS : a derivative of Mandriva, grew from a group of packages into a community-spawned desktop distribution.
- Red Hat Enterprise Linux : which is a derivative of Fedora, maintained and commercially supported by Red Hat.
- Sabayon Linux : Gentoo Based Distribution, aiming at working Out of the box.
- SimplyMepis : a Debian-based distribution intended for easy desktop use and strong support.
- Slackware : one of the first Linux distributions, founded in 1993, and since then actively maintained by Patrick J. Volkerding.
- Suse Linux Enterprise : derived from openSUSE, maintained and commercially supported by Novell.
- Ubuntu : a popular desktop and server distribution derived from Debian, maintained by Canonical Ltd..
- Xubuntu : is the Xfce version of the popular desktop distro Ubuntu. Commonly used by Linux users that wish to have the function of a bigger distro such as Ubuntu or openSuse with the speed of a smaller distro.
- Puppy Linux
- Slackware
- Antix
- Backtrack
Installation
There are many ways to install a Linux distribution. The most common method of installing Linux is by booting from a CD-ROM or DVD that contains the installation program and installable software. Such a CD can be burned from a downloaded ISO image, purchased alone for a low price, provided as a cover disk with a magazine, shipped for free by request, or obtained as part of a box set that may also include manuals and additional commercial software. New users tend to begin by partitioning a hard drive in order to keep their previously-installed operating system. The Linux distribution can then be installed on its own separate partition without affecting previously saved data.
Early Linux distributions were installed using sets of floppies but this has been abandoned by all major distributions. Nowadays most distributions offer CD and DVD sets with the vital packages on the first disc and less important packages on later ones. They usually also allow installation over a network after booting from either a set of floppies or a CD with only a small amount of data on it.
Still another mode of installation is to install on a powerful computer to use as a servers and to use less powerful machines (perhaps without hard drives, with less memory and slower CPUs) as thin clients over the network. Clients can boot over the network from the server and display results and pass information to the server where all the applications run. The clients can be ordinary PCs with the addition of a network bootloader on a drive or network interface controller; hard disk space and processor power can be offloaded onto the client machine if desired. The cost savings achieved by using thin clients can be invested in greater computing power or storage on the server.
In a Live CD setup, the computer boots the entire operating system from CD without first installing it on the computer's hard disk. Some distributions have a Live CD installer, where the computer boots the operating system from the disk, and then proceeds to install it onto the computer's hard disk, providing a seamless transition from the OS running from the CD to the OS running from the hard disk.
Both servers and personal computers that come with Linux already installed are available from vendors including Hewlett-Packard and Dell.
On embedded devices, Linux is typically held in the device's firmware and may or may not be consumer-accessible.
Anaconda, one of the more popular installers, is used by Red Hat Enterprise Linux, Fedora and other distributions to simplify the installation process.
Installation via an existing operating system
Some distributions let the user install Linux on top of their current system, such as Winlinux or coLINUX. Linux is installed to the Windows hard disk partition, and can be started from inside Windows itself.
Virtual Machines (such asVirtualBox or Vmware ) also make it possible for Linux to be run inside another OS. The VM software simulates a separate computer onto which the Linux system is installed. After installation, the virtual machine can be booted as if it were an independent computer.
Various tools are also available to perform full dual-boot installations from existing platforms without a CD, most notably:
- The Wubi Installer, which allows Windows users to download and install Ubuntu or its derivatives without the need for hard drive partitioning or an installation CD, allowing users to easily dual boot between either operating system on the same hard drive without losing data
- Win32-loader, which is in the process of being integrated in official Debian CDs/DVDs, and allows Windows users to install Debian without a CD, though it performs a network installation and thereby requires repartitioning
- UNetbootin , which allows Windows and Linux users to perform similar no-CD network installations for a wide variety of Linux distributions and additionally provides live USB creation support .
